Coring device



Y below the valve III is a barrel ll having a lowe Patented June 15,

UNITED. STATES PATH Ni t nes CURING nnvrcn B ia-mIn W. Sewell, Tulsa, Okla, assignor to 7 Standard Oil Development Company, a corpo ration of Delaware Application December as, 1941;, Serial sea ants. (Cl. 255-72) 3 Claims.

The presentinvention is directed to-a pressure coring device. 4

- The principal object of present invention is the provision of a device of thecharacter deof the porpressure or, if desired, maybe partiallyevacm ated. When the coring operation is completed,

a weight '24 is dropped on the head 2|. ThlS -weight may be dropped fr'ornthe surface or it "may be suspended in the drill stem'b'y a wire line at a suflicient distance above the head so that,

when it drops on the head, it will exercise enough 2 force to move the stem is downwardly removing designates a drill stem carrying at its lower end v a head 2 which is-provided withoircumferentially disposed cutters 3 for cutting the core, said cutters surrounding a central passage 4 through which the core passes as it is cut.

Mounted in the head 2 is a rotatable valve- 5 having a central passage 6 adapted to align with maze d, This .valve iscarried by the lower end'of a cylinder 1 andis of the typeshown in Patent No.. 2,216,962, issued October 8, '1940, in which is disclosed in detail the operating mechanism for this valve.

a stem 9. The lower endof the stem carries a The cylinder I has an opening 8 at its upper endthrough which passes the valve i8 from its seat. The drilling mud which sosed in the drilling operation enters the compartment [5 through the inlet ports 23 and exerts a-pressure behind the piston 22. .As

soon ss-valve l8 is removed from its seat, the

drilling mud pressure, which may be several thousand pounds, will immediately force the piston 22 upwardly into the compartment l5 carstem I and the barrel lLwithit. The parts 'are so proportioned that the piston will travel a suflici ent distance to seat the valve I ll thereby sealing c1! theupper endof chamber].

' As soon as the barrel ii is withdrawnirom the central passage of the valve 5, thisvalve is closed by the mechanism heretofore referred to and .described-in Patent No. 2,216,962. Chamber 1 is then completely sealed and is brought to the sur' While the present invention has been described in connection with-adrill stem core barrel, it will cone valve I 0 which is'adapted to the seat on the underside of opening 8. Carried by the stem 9 open end adapted to communicate with arms l2 constituting a core catch Mounted in the drill stemabove. cylinde'r'l is a second cylinder vl3 having an upper compartment I4 and a lower compartment-iio separated by a partition 18 having a central opening ll,

ing gland 2! and to the-exterior where it terminatesinaheadfl.

The stem 2 extends'through the bottomfwall of compartment l5 and terminates in'a piston 22. The lower wall oi compartment it below the piston 22'is provided with inlet ports 23.; Compartment II is normally filled with oil.

4 and being provided at its lower end withsp' be apparent that it is also applicable to wire line core barrels. It is to be understood that various changes in design and relationship of parts-are contemplated within the scope of the present in- 'vention, the embodiment above described being.

purely illustrative.

i The nature and objects of the present invention having been thus described and illustrated, what is claimed as new and useful secured by letters Patent is:

(- The dorms device illustratedis. lowered into 'thewellwith thepartsinthepositionshown. Compartment I4 i filled 1'. A pressure coring device comprising a fontting head adapted to cut a core and having a cenr tra'l passage adapted to receive the core, a. cor the lower portion of which constitutes a seat 7 7' e for a cone valve I. carried by a stem l9'extending up through compartment ll through a packreceivlng barrel arranged behind said cutter head adapted to assume a forward position ands retracted position "and arranged for communication with said e' when in its forward position, means for holding said barrel in its forward position during thecoring operation, means operable by a falling weight tomove said barrel formation cored.

with air at atmospheric 2. A pressure coring device comprising" a cutand is desired to be its retracted position upon completion ofthe a I w ting head adapted to cut a core and having a central passage adapted 'to receive the core, a

core-receiving barrel arranged behind said cutter head adapted to assume a forward position and a retracted position,and arranged forcommunication with said passage when in its forward position, means for holding said barrel inadapted to assume a' forward position and a retracted position and arranged for communication with said passage when in its forward position, means for holding said barrel in its forward position, including a piston rigidly connected to said barrel, a cylinder in which said piston works adapted to be filled with a fluid to hold said piston in its outermost position, said piston having its outer face exposed to a pressure at least as great as the pressure of the formation being cored; means for releasing the fluid from said cylinder whereby said piston is pushed into said i cylinder by the pressure acting on the outer face and said barrel is moved to its retracted position, and means operable upon movement of said barrel to its retracted position for sealing said barrel under the pressure of the formation cored.

BENJAMIN WJSEWELL. 

